Heritage Research Group Announces State Route 101 Collaboration

The Heritage Research Group partnered with two THG companies – Asphalt Materials, Inc. and Pavement Maintenance Systems – to reconstruct nine miles of the highway in an efficient and cost-effective manner for the Indiana Department of Transportation (INDOT).

Heritage Research Group was responsible for the mix design and Just-In-Time Training (JITT), Asphalt Materials, Inc. supplied the engineered asphalt emulsion, and Pavement Maintenance Systems produced the CCPR mix.

After years of collaboration with contractors, material suppliers, and consultants including Heritage Research Group, INDOT issued new construction specifications for pavement recycling in May 2017. Utilizing these specifications, INDOT decided to reconstruct SR101 using both Full Depth Reclamation (FDR) and Cold Central Plant Recycling (CCPR) in April 2018.

Through INDOT’s vision, the existing 22-foot wide hot mix asphalt pavement was milled and transported to a nearby location for later processing. The remaining pavement structure, along with each shoulder, then underwent a cement FDR treatment to widen the roadway to 26 feet.

In this process, the remaining pavement, aggregate base, and subgrade were pulverized and mixed with cement to stabilize and create a foundation for the remainder of the pavement structure. Using a specialized mobile mixing plant, owned and operated by Pavement Maintenance Systems, the existing pavement millings were mixed with an engineered asphalt emulsion produced by Asphalt Materials’ Oregon, Ohio terminal.

The CCPR mix was then transported back to the roadway where Brooks Construction Co, Inc. laid 37,000 tons of CCPR mix using conventional paving equipment. After final curing of the CCPR mix, Brooks Construction Co, Inc. paved 2 inches of hot mix asphalt (HMA) to serve as a surface course for the roadway.

The pavement structure that INDOT selected for SR101 is best described as “green pavement.” The newly constructed pavement consists of approximately 90% recycled materials from the existing roadway. In addition to the use of recycled material and the

in-place construction of the FDR, the close-proximity of the mobile mixing plant allowed for efficient use of transportation resources.

The story of SR101 is an example of how The Heritage Group continues to be a leader in road construction projects, building roadways, providing value to agencies, and forever improving the performance of pavements in an environ- mentally and economically friendly way.